Charles w



Patented Jan; 2, 1894.

Inn/eaten: Charles W C'a'ntz hi6 flit ys 4 1 v I 5 w mtnesses 9Q NITEDSTATES FFICEQ' CHARLES W. OANTZ, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNORTO HENRY DISSTON 82; SONS, INCORPORATED, OF SAME PLACE.

lNGOT-CASTING MOLD.

SPECIFICATION forming part of Letters Patent No. 512,005, dated January2, 1894. Application filed October 12, 1891. Serial Ila/08,421. (Nomodel.)

To all whom it may concern.-

Be it known that 1, CHARLES W. OANTZ, a citizen of the United States,and a resident of Philadelphia, Pennsylvania, have inventedcertainlmprovements in Ingot-OastingMolds, of which the following is aspecification.

' The object of my invention is to provide for the casting of steelingots free from blowholes and impurities and Without cracks orfissures, or as they are technically termed pipes, and this object Iattain by the use of a special formof mold cap in the manner hereinafterset forth, reference being had to the accompanying drawings, in whichFigures 1, 2, 3 anderepresent the successive stages in the formation ofan ingot in accordance with my invention.

Before proceeding to pour the molten steel into the ingot mold A, Iplace in the bottom of the mold a bucket B of refractory material, whichhas a handle 1) whereby it may be readily lifted from orlowered into themold, the bucket also having, in the bottom, one or more openings a. Themolten steel is poured from the crucible D into this bucket, which,itshould be understood, has been heated to a white heat before beingplaced in the mold, and the metal passes through the opening or openingsin the bottom of the bucket and gradually fills the mold,the bucketfioatingon the top of the metal as the latter rises. This serves toprevent the blow-holes in the ingot, such as are caused by the splashingof the molten metal when poured directly into the mold, the metalpassing through each opening in the bottom of the bucket in the form ofa solid stream, so that the mold is filled without any disturbance ofthe metal, the bucket also serving to retain any impurities which mightotherwise be caught and held by the metal in the mold. The use of thebucket also prevents the rapid destruction of the mold which is causedby the pouring of the molten steel directly into the same. It should bestated, however, that the use of this bucket forms no part of my presentinvention, its use having been described only as incident to theproduction of a perfect mass of metal in the body of the ingot, myinvention relating to a special form of cap for the mold whereby areserve supply of molten metal is provided for the purpose of preventingfissures in the ingot. After the ingot mold has been almost filled withthe molten metal, the bucket B is removed and a hollow cap F, also ofrefractory material and heated to a white heat, is placed upon the topof the molten metal as shown in Fig. 2, sand or other luting material dbeing thrown onto the top of the mold to close the space between thesame and the sides of the cap. In the top of the hollow cap Fis a seriesof openingsf, preferably two openings arranged as shown, and through oneof these openings the molten metal is now poured, as shown for instancein Fig. 3, so that the metal partially or completely fills said hollowcap the air escaping through the other opening. The formation of cracksor fissures, or as they are technically termed pipes in steel ingots iscaused by the fact that the ingot cools and hardens first at the sidesand bottom, the center of the ini got being the last to become hard.Hence the fissures due to the shrinking of the metal are in the centerof the ingot and extend from the top of the same downward into the bodyof the ingot to a greater or less extent. The metal in the hollow cap F,however, provides a reserve supply which will compensate for anyshrinkage in the body of the ingot, that is to say, this reserve supplyof metal being inclosed in the highly heated cap F is the last to cool.Hence any piping due to the shrinkage of the metal will be formed in themetal in the cap, as shown in Fig. 4, and not in the ingot itself. Inorder that this result may be effected, however, it is necessary thatthe metal should be at liberty to fiow with perfect freedom from the capinto the mold, any restriction of the area of the passage such as wouldbe caused by the partial closing of the bottom of the cap being fatal tothe proper attainment of the object of the invention. The use of atleast two openingsin the top of the cap is also necessary in order toinsure the proper flow of the metal into and its rise in the cap, oneopening providing for the inflow of the metal, and the other for theescape of the air. Each of the openings can notsuch as 'to lead to therapid chilling of the metal in the upper portion of the cap.

In order to maintain the upper and central portions of the mass of steelin the cap in a molten condition as long as possible, the top of the capis much thicker than the sides, so

that said top will retain the heat longest.

Having thus described my invention, I claim and desire to secure byLetters Patent- The combination of an ingot mold with a hollow caphaving two or more contracted openings in the top and an uncontracted0pe11- ing in the bottom for the flow of the molten metal from the capinto the mold, substan- 15 tially as specified.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

CHARLES WV. OANTZ.

Witnesses:

HARRY SMITH, HENRY HowsoN.

